Brønsted acid activation strategy in transition-metal catalyzed asymmetric hydrogenation of N-unprotected imines, enamines, and N-heteroaromatic compounds.

摘要: Asymmetric hydrogenation plays an important role in organic synthesis, but that of the challenging substrates such as N-unprotected imines, enamines, and N-heteroaromatic compounds (1H-indoles, 1H-pyrroles, pyridines, quinolines, quinoxalines) has only received increased attention past three years. Considering interaction modes a Bronsted acid with Lewis base, acids may be used ideal activators C=N bonds. This Minireview summarizes recent advances transition-metal-catalyzed, activated asymmetric these substrates, thus offering promising substrate activation strategy for transformations involving